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I have a '02 998 and are considering a light flywheel. Does anyone have any thoughts or experience with this mod. I have ridden 996s and find the stock 998 winds up much quicker, so I guess the flywheel has been lightened some. I wouldn't want to over do it. I been shopping around on the net and have found a German company that makes one, well I think I've found one. They call it an ignition rotor I'm not sure about it. Sure looks like a nichols flywheel. Anyway it not as light as the nichols version but lighter than stock.
 

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if you don't want to go as light as a nichols there's no reason to spend money on one when you can have yours lightened for a fraction of the cost. that's what i'd do if i didn't already have the nichols.
 

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The plus of a lighter flywheel is quicker revving, or an eager feeling. Your description of your 998 sounds like Ducati has lightened the flywheel.

The minuses are a slightly poorer idle and additional instability in the valvetrain from the power pulses shock loading the cam drive. This is probably why Ducati went to rubber belts. Many singles and V-twins show a bit more HP with a heavier flywheel.

Will yours show any of the bad traits? maybe, but probably not enough to notice after you turn up the idle.

I just had a lot of work done on my 748. They turned the flywheel and removed maybe 2 pounds. It stalls a lot, but I like it.
 

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Colt45 said:
Many singles and V-twins show a bit more HP with a heavier flywheel.
i heard this once before and have yet to see any proof...or even a logical explanation. can you provide further information on this or point me in the direction of some late night reading.
 

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Colt45 said:
The plus of a lighter flywheel is quicker revving, or an eager feeling. Your description of your 998 sounds like Ducati has lightened the flywheel.

The minuses are a slightly poorer idle and additional instability in the valvetrain from the power pulses shock loading the cam drive. This is probably why Ducati went to rubber belts. Many singles and V-twins show a bit more HP with a heavier flywheel.

Will yours show any of the bad traits? maybe, but probably not enough to notice after you turn up the idle.

I just had a lot of work done on my 748. They turned the flywheel and removed maybe 2 pounds. It stalls a lot, but I like it.

Who did the work?
 

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Colt45 said:
Many singles and V-twins show a bit more HP with a heavier flywheel.
That seems odd.. I´m not saying your wrong, It´s just that i have heard the opposite. After searching the net i found this..

This is an ST2 with before and after runs with a light flywheel.

Red is Lightened Flywheel
Green is "Normal" flywheel

Times acceleration


Power and Fuel/Air


NOTE: this ST2 was quite heavily modified enginewise and correction factors are NOT used in the first graph.
http://www.moto-one.com.au/performance/st2hicomp.html
 

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If I'm reading it right the first graph is acceleration run and the lightened flywheel is actually slower
 

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yeloduke said:
If I'm reading it right the first graph is acceleration run and the lightened flywheel is actually slower
yeah, almost imperceptibly. but the St2 is a 2-valve and not a superbike. the st2 is a whole nother kind of creature, more like a transport plane.


back to flywheel, you're on a 998 and i haven't ridden one, were you on a 748,916,, i'd say pull it altogether on the single-phase, and lighten as much as possible on the 3-phase 996.

as long as your not a spazz on the throttle you shouldn't have a real issue. what the other guys mentioned is right on. i'm just chiming in because i pulled mine on friday and wish i'd done it long ago...but the engine breaking will increase which is the only draw back. to me less is better
 

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Amullo,

http://www.moto-one.com.au/performance/dyno.html

Moto-One uses an inertia dyno that calculates power from acceleration, like most DynoJets. Lighter tires as well as lighter flywheels show more power on these dynomometers.

The way around that problem is with a DynoJet 250 or equal that can hold a steady speed or RPM. You work up the pull in stair steps with a hard pull at each RPM. Inertia is taken out of the equation, then, but cooling becomes an issue.

RI749,

The DucShop did a superb job. I had an 853 kit installed with a blueprint.
 

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yeloduke said:
If I'm reading it right the first graph is acceleration run and the lightened flywheel is actually slower
Correct, but if you read the article about lighter flywheel´s you´ll see that the conditions where diffrent and the dyno doesn´t use correction factors for the acceleration times, but it does with the HP/fuel-air graph.



Colt45 said:
Amullo,

http://www.moto-one.com.au/performance/dyno.html

Moto-One uses an inertia dyno that calculates power from acceleration, like most DynoJets. Lighter tires as well as lighter flywheels show more power on these dynomometers.

The way around that problem is with a DynoJet 250 or equal that can hold a steady speed or RPM. You work up the pull in stair steps with a hard pull at each RPM. Inertia is taken out of the equation, then, but cooling becomes an issue.

RI749,

The DucShop did a superb job. I had an 853 kit installed with a blueprint.
Yepp.. i figured that. Brad also states that the ST2 felt much quicker with the lighter flywheel on it.

But getting back to the basic question. The reason why the 998 feel´s "revvier" is that it´s got a whole new "revvie" engine design compared to the old Desmoquattro in the 996S.

//amullo
 

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Discussion Starter #11
But getting back to the basic question. The reason why the 998 feel´s "revvier" is that it´s got a whole new "revvie" engine design compared to the old Desmoquattro in the 996S.

//amullo[/QUOTE]

I read a comparison article on the engines (996 vs 998) completely different engine and computer sytem yes , but having experienced both models the only difference in straight line performance that I notice was the acceleration of the 998 was much quicker but once up to speed the 996 was right there. Leading me to believe the flywheel plays a role in the 998 performance differential. Just a guess.

Thanks to everyone for the replies the majority all seem positive of the flywheel mod.
 

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JAC said:
I have a '02 998 and are considering a light flywheel. Does anyone have any thoughts or experience with this mod. I have ridden 996s and find the stock 998 winds up much quicker, so I guess the flywheel has been lightened some.
Well Duh?

The 998 has a bore and stroke of 100mm X 63.5mm
The 996 has a bore and stroke of 98mm X 68mm

Flywheels being equal the 998 is going to spin up much faster naturally.
By the way the stock 998/999 flywheels are heaver than the stock 996 flywheels due to the short stroke motor!
The bigger valves aid the 998 in reaching higher rpms, faster as well!

Never compare apples and oranges to one another.
 

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Pinocchio said:
Well Duh?

The 998 has a bore and stroke of 100mm X 63.5mm
The 996 has a bore and stroke of 98mm X 68mm

Flywheels being equal the 998 is going to spin up much faster naturally.
By the way the stock 998/999 flywheels are heaver than the stock 996 flywheels due to the short stroke motor!
The bigger valves aid the 998 in reaching higher rpms, faster as well!

Never compare apples and oranges to one another.

Interesting - is this based on the assumption that the shorter stroke crank has less crank inertia (probably a valid assumption, all else being equal) - or are you suggesting there's some other inherent reason why a short-stroke motor will spool up faster?
 

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Anyone know if the 999Rs flywheel is stock? There really is no info on line that I can find on the 2006 models. The shop told me the fly wheel was lightend, but I tend to wonder if they know anything anymore after they messed up on my clutch, and dont return calls. I know it has a lighter crank
 

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The 999R has a diffrent stroke x Bore to the 999S model, so I´m guessing that the weight of the flywheel differs from the S or BiP models of the 999. If it´s lighter or heavier i have no idea, but givven the stroke x bore and the "race" implication of the R models, my guess would be lighter.

I helped emullo put on a 254gram flywheel this weekend on his 996S (EU). This is actually the EXACT same flywheel for both the Desmoquattro AND the Testastretta 996R.. The same ID in the workshop catalogue and the same order number at Ducati Kaemna in Germany..

So Ducati doesn´t fool around with a design that works. The flywheel on the late desmoquattro and early Testastretta are the same.. Makes you think.

//amullo
 

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I installed a Nichols in my 996 motor, and was initially very disappointed in the affect on the street. Seemed to make the bike VERY susceptible to low-speed roughness and jerkiness on light throttle - cruising through residential streets at 40-50 or so.

Since I reset the TPS, and synced the TBs the bike is much smoother, although there's stilla lot of shudder down below 4K RPM on any high-gear acceleration - something I guess one learns to avoid by revving the motor higher than what is necessary with the stock heavy flywheel. Regardless, I would not switch back to the stock unit, as I really like the feel of the extra response and willingness to rev.

Whether it's really any faster overall on the track, is an unknown to me, but it FEELS faster - and that's a cool thing. ;)
 

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+1 on that Old Baldy!! I have a Nichols on my 04 999r and love it. The stock flywheel was huge and heavy. With the Nichols turn in is very noticably quicker and the fun starts at 5K instead of 6K as with the stock flywheel.
6th gear feels like fifth used to, way big fun. Spin up is lots quicker so be careful with that trottle on corner exits.
Very true about the rough running below 5K on my bike. Ducatis want to run
not putt around and when you make modifications like lighter flywheels it make this even more so. I had an issue with stalling but according to the shop they have the problem solved. I can hardly wait to pick it up and go for a ride.
 

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The idle issue comes up every time someone asks about light flywheels, and I think it's hogwash. I have a Nichols light flywheel in my 996, and am also running sps cams, light rods/pistons, light crank and lightweight flywheel, and I have ZERO idle problems. The only downside I can document is the bike can be a real b!tch starting from a stop, and will stall if you don't feather the clutch and give it enough gas. If a bike that has a light flywheel has idle problems, it's a tuning issue, not a flywheel issue.
 

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Let's put this to rest - I got a Nichol's flywheel and had it installed by Nichols. Make sure you use the double locking nuts (also by Nichols.) If you cruise on your 998 (which I really hope you don't coz then we'll just have to take that bike away from you for not being worthy of it) Nichols flywheel is not for you. If you rider canyons, tracks and such, faster accelleration and engine braking are your friends. Get the Nichols flywheel, it's the best one on the market - you will love it.
Another thing - Nichols installed the flywheel and they tuned my bike (idol speed) to match the flywheel - I have not had ANY probelms AT ALL with any kind of stalling or any issues with it. I guess it's not just a "plug and play" upgrade, so make sure people installing it know what they are doing.
 
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